Which of the following is an example of a mechanical wave?

Sound waves are classified as mechanical waves because they require a medium—such as air, water, or a solid material—to travel through. In the case of sound, the wave generates vibrations that compress and rarefy particles in the medium, transmitting the energy along the wave's path. This interaction is fundamental to how sound is produced and propagated.

In contrast, the other options are forms of electromagnetic radiation. X-rays, light waves, and radio waves do not rely on a medium for transmission. They can travel through the vacuum of space because they consist of oscillating electric and magnetic fields, allowing them to move independently of material substances. This distinction is crucial in understanding the different categories of waves and their behaviors in various environments.